1. Field of the Invention
The invention generally relates to a projection device.
2. Description of Related Art
A projector is a display device for generating a large size image. The projector is to convert an illumination beam generated by a light source module into an image beam through a light valve, and then project the image beam onto a projection screen or a wall surface through a projection lens, so as to form an image. As advances in projection technology and a reduction in manufacturing cost, the applications of the projector have extended gradually from commercial uses to family uses.
The projector is usually placed on a desktop, hanged under the ceiling via a support frame, or set up on the ground. In addition, in terms of power supply, the projector is usually connected to a power outlet (e.g., an indoor power socket) through an independent power cord.
In order to generate illumination beams of different colors such as three primary colors (red, green and blue), the projector may uses multiple (e.g. three) light-emitting elements (e.g., LEDs or other solid state light sources) for respectively providing the color beams (e.g. the illumination beams of three primary colors). The light-emitting elements are usually thermally coupled to a heat dissipation module, such as a heat sink or a heat dissipation fin, so as to discharge heat generated during operation. Because each light-emitting element would generate heat and has its temperature when providing illumination beams of the corresponding color, if multiple light-emitting elements thermally coupled to the same one heat dissipation module, the temperature of one light-emitting element may increase due to receiving heat generated from other light-emitting element, and thereby the operation lives of the light-emitting elements will be affected.
In order for heat dissipation, the projector may use active airflow provided by a fan with the heat dissipation module to cool the light-emitting elements, so as to prolong the lives of the light-emitting elements. However, the fan may produce noises during operation.
The information disclosed in the “BACKGROUND OF THE INVENTION” section is only for enhancement of understanding of the background of the described technology, and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Further, the information disclosed in the “BACKGROUND OF THE INVENTION” section does not mean that one or more problems to be resolved by one or more embodiments of the invention was acknowledged by a person of ordinary skill in the art.